Sketcher grid

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drmacro
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Re: Sketcher grid

Post by drmacro »

rascalito wrote: Thu Oct 28, 2021 12:54 pm ...The first one (bottom) is perfect.
...
No it is not perfect. None are constrained.

Since you should constrain all geometry in a sketch, you have gained little by snapping to the grid.


Using the ctrl key restricts the arcs to 90 degrees. So, if your first edge is added with a horizontal or vertical, then using ctrl key make an arc 90 degrees and the next line is going to be orthogonal to the first.

In addition, drawing a rectangle of this shape is far faster using the rounded rectangle tool.
Peek 2021-10-28 09-31.gif
Peek 2021-10-28 09-31.gif (534.03 KiB) Viewed 932 times
In the end you should use what you feel comfortable with. :mrgreen:
Star Trek II: The Wrath of Khan: Spock: "...His pattern indicates two-dimensional thinking."
rascalito
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Re: Sketcher grid

Post by rascalito »

Hello!

Thanks for your reply!

By perfect, I meant that the first draft is exactly on grid, not the others.
I still have a lot to learn, I'm in my second week of using Freecad and not even full time.
Thanks for the rounded rectangle, I wasn't aware of it. I used to do it using the center
symmetry. This time, I did it to test the polyline tool only.
In the end you should use what you feel comfortable with.
Yes, I guess it's the idea.
openBrain
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Re: Sketcher grid

Post by openBrain »

rascalito wrote: Thu Oct 28, 2021 11:23 pm Hello!

Thanks for your reply!

By perfect, I meant that the first draft is exactly on grid, not the others.
First, be aware that while sketcher snaps points on the grid, it absolutely not locks them on the grid. As soon as you will add constrains, sketcher will compute point positions without caring if they are one the grid or not.
Also, shaping is sketcher is before all based on constrains. So you should not be afraid to have a "dirty" shape when you just drew. After that you have to apply geometrical constrains to define and lock the shape, then finally the dimensional constrains to give the shape the correct size. That's why grid is generally not advised. While it makes the sketch look perfect for human eyes, it is absolutely from CAD flow point of view. ;)
rascalito
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Re: Sketcher grid

Post by rascalito »

Hello!

Thanks for your reply!
Yes, I'm aware that the only thing that counts is basically the constraints. But as the grid exists and existed
before I started using it, I'm probably one of zillions of people who actually use it. It might be less important
for people who design real 3D shapes. I don't. I'm doing basically 2.5 D shapes (that can be milled with a 3 axis
CNC, no spherical shapes, etc). And since the only purpose of what I design is to hold together PCBs that I also
design, most of the dimensions are integral numbers in mm. Therefore the grid is really quick for me.
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Shalmeneser
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Re: Sketcher grid

Post by Shalmeneser »

rascalito wrote: Fri Oct 29, 2021 9:09 am Therefore the grid is really quick for me...
... and dirty.
You should try to constraint all yours sketches.
rascalito
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Re: Sketcher grid

Post by rascalito »

Hello!

So you assume I don't constrain anything?
Might be surprising, but I constrain everything until the color changes, purple for the construction lines and
green for the others. Nevertheless, I'm glad the grid (and snap thereof) exist because it saves me time.
drmacro
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Re: Sketcher grid

Post by drmacro »

rascalito wrote: Fri Oct 29, 2021 11:20 am Hello!

So you assume I don't constrain anything?
Might be surprising, but I constrain everything until the color changes, purple for the construction lines and
green for the others. Nevertheless, I'm glad the grid (and snap thereof) exist because it saves me time.
I think we should stop this thread. It is clear you are using what you've decided is right for you. This a good thing, it would be bad if it was likely to cause some explicit grief or error, but, that is not the case with using the grid. It is there to be used, or not, as the user sees fit.

Seasoned users have shared their opinion and you have made it clear you understand their offered options, but prefer your workflow.

That is fine. I'm guessing @Shalmeneser guessed from previous images in this thread that constraining was not being used. It was not a specific topic of discussion and was not explicitly defined either way.
Star Trek II: The Wrath of Khan: Spock: "...His pattern indicates two-dimensional thinking."
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Shalmeneser
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Re: Sketcher grid

Post by Shalmeneser »

drmacro wrote: Fri Oct 29, 2021 11:49 am That is fine. I'm guessing @Shalmeneser guessed from previous images in this thread that constraining was not being used.
True. If the sketch is constrained after, no problem.
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